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Heroes: Alan Turing
Turing was described as scruffy and eccentric
AlanTuring
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ThemathematicianwhocrackedGermany’ssecret codesandsavedthelivesofmillions
Code-breaking played a fundamental part in the Allied forces’ victory in the Second World War. The Germans had inventedan‘Enigmamachine’,whichwasused toencryptsecretmessagescontaining importantmilitaryinformation,suchasthe positionsoftheirdeadlyU-boats.Whena messagewastypedintothemachine,itwas scrambledintooneofnearly159quintillion(159 billionbillion)possiblecombinations.Todothis, itusedanalgorithm,or‘key.’Thekeywouldbe changedevery24hours,makingitextremely difficultforeventhemostbrilliantmindsto decipherthemessages.
Buttherewasonemindthatdidsucceed,and itbelongedtoamannamedAlanTuring.Bornin 1912,Turinghadarelativelyprivileged upbringing,attendingarenownedindependent schoolinDorset,England,beforestudying mathematicsatCambridgeUniversity.Hewas awardedafirstandwaselectedafellow,andin 1936hecameupwiththeideafora programmablecomputerknownasa‘Turing machine.’Withit,heprovedthatany mathematicalproblemcouldbesolved,aslong asitwasrepresentableasanalgorithm.Many arguethismachinewasthemodelforall moderncomputers.
Turingthenbeganworkingpart-timeforthe GovernmentCodeandCypherSchool.Onthe outbreakoftheSecondWorldWar,Turingwas givensecretorderstoreporttoBletchleyPark, anageingmansioninBuckinghamshire.Little didheknowitwastobecomethecentrefor Britishwarintelligence.
BuildingonPolishresearchintotheEnigma code,heandmathematicianGordonWelchman developedanelectromechanicalmachinecalled
Alife’s work
Thehighsandlowsof AlanTuring’sremarkable lifeandcareer
1912
Turingisbornin LondontoJulius andEthelTuring, whileJuliusison leavefromthe IndianCivilService.
1931
Turingis acceptedinto CambridgeUniversitytostudy mathematicsandgraduates withaFirstthreeyearslater.
1938
TheGovernment CodeandCypher SchoolemployTuringparttimetoworkoncryptanalysis oftheEnigmacode.
1939
Warbreaksoutand TuringispostedtoBletchley Park,thecentralsitefor Britishintelligence.
The Bombe
Many of the messages encrypted by the Germans contained a short piece of predictable text, such as ‘Heil Hitler.’ When cryptographers at Bletchley Park thought they had found some of this text, they would analyse it to produce a ‘menu’ – a graph consisting of letters linked up like a London Underground map. This would then be passed onto a Bombe operator, who would wire up the letters on the machine according to the menu. The Bombe was then set running, and ever so often it would stop and the operator would write down the possible password, or ‘key’, it had found. This was then tested to fi nd out if it was the correct one.
A statue of Turing made entirely of slate still stands at Bletchley Park The bombe’s rotating drums mirrored the rotating discs on the Enigma machine
a‘Bombe.’Though the Poles had succeeded in readingEnigma messages on the simplest key systems,thismachine allowed any message to bedeciphered, so long as the hardware of the Enigmawasknown and a plain-text ‘crib’ of about20letters could be guessed correctly. It is believedthatTuring’s work shortened the war in Europebyatleast two years.
Afterthewar, Turing worked on the design foranAutomatic Computing Engine (ACE), whichperformed its fi rst program in 1950. He alsowroteachess program, in which the computertook about half an hour to make each move.However, his work was interrupted in1952,when he was charged with gross indecency for having a sexual relationship withaman. Turing pleaded guilty, but ratherthan face prison, he agreed to undergo hormonal treatment. If that were not punishment enough, he was also banned from continuing his work for the government. Two years later, he tookhis own life. In 2013, Turing was grantedapardon under the Royal
Prerogative of Mercy after a campaign supportedby thousands, including Professor StephenHawking.
Top 5 facts: Alan Turing
1He was a talented distance runner
Turing was a keen sportsman, and his best marathon time of two hours and 46 minutes was only 11 minutes slower than the time clocked by the winner in the 1948 Olympic Games.
2He was an eccentric Scruffy and nail-bitten, Turing was renowned at Bletchley for being an eccentric; he chained his coffee mug to the radiator so that no one else could use it!
3He proposed to a Bletchley co-worker
In 1941, Turing proposed to Hut 8 coworker Joan Clarke, but ended the engagement after admitting he was homosexual.
4He was an unsung hero
Even after the war, the British authorities couldn’t reveal they had cracked the Enigma code, so his work was unknown to the public until decades after his death.
5He received a government apology
In 2009, British Prime Minister Gordon Brown issued an offi cial apology for his prosecution, saying “you deserved so much better.”
In theirfootsteps…
Genevieve Feinstein
Feinstein was an American Signal Intelligence Service cryptanalyst, involved in the decryption of Japanese messages sent during WWII. In 1940, she made a discovery that enabled the SIS to build an analogue decipher machine. Following the war, she worked on a US project called ‘Venona’, decrypting information sent by Soviet Union intelligence agencies.
Clifford Cocks
A British cryptographer, he discovered one of the fi rst public-key cryptosystems, known as RSA. It can encrypt messages, which can then be deciphered by the receiver without either party requiring secret keys. Developing it in 1973, he kept the information secret. It was rediscovered and published by three American mathematicians, who named RSA after themselves.
1940
The fi rst codebreaking ‘Bombe’ machine is installed at Bletchley Park.
1942
Turing travels to the USA to work on the Naval Enigma and Bombe construction in Washington.
1945
Turing is awarded an OBE for his contribution to the war effort, but his work remains secret for many years.
1948
Appointed Reader in the Mathematics department at the University of Manchester, he begins writing a chess computer program.
1952
Turingpleadsguiltyto grossindecencyforhaving asexualrelationship withamanandbegins hormonetreatment.
1954
Turingcommits suicidebycyanide poisoning,aged41.
